Dried Fondant

I have a bunch of dried fondant flowers and a Fondant letter topper that is going on a cake today. My question is if this cake is put in the refridgerator for atleast 7 hours will the fondant start to rehydrate and become soft? Will my letter topper break of sag? They have been drying for atleast three days. I only ask because I have to deliver at about 10:00 this morning and they won't eat it until about 5:30. It's an all buttercream cake with the dried fondant flowers. Thanks for everything!Lisa